调试易

            openFileDialog1.Filter = "文本|*.txt";
            if (openFileDialog1.ShowDialog() == DialogResult.OK)
            {
                string _OpenFilePath = openFileDialog1.FileName;
            }            saveFileDialog1.Filter = "文本|*.txt";
            if (saveFileDialog1.ShowDialog() == DialogResult.OK)
            {
                string _SaveFilePath = saveFileDialog1.FileName;
            }

新建就是把输入框清空，保存就是直接保存，另存为就是调用saveFileDialog获取路径后保存

就是像系统自带的记事本，它的新建和另存为是如何实现的？ 
给你的Form添加MenuStrip还有就是，opendialog和savedialog如何用呢？ OpenFileDialog openFileDialog = new OpenFileDialog();
 string  FileName;
             if  ( this .openFileDialog1.ShowDialog()  ==  DialogResult.OK)
              {
              FileName  =   this .openFileDialog1.FileName;
               if  (FileName  !=   "" )
                {
                 this .pictureBox1.Image  =  Image.FromFile(FileName);
              } 
            } 
SaveFileDialog dlg = new SaveFileDialog();if (dlg.ShowDialogue() == DialogueResult.OK)
{
     dlg.FileName = fileName;
     // ........
      return dlg.FileName; // Don't return that first filename string
} 

TextBox 控件, 选择多行属性.  存在数据库中

openFileDialog1.Filter = "文本|*.txt"; 
            if (openFileDialog1.ShowDialog() == DialogResult.OK) 
            { 
                string _OpenFilePath = openFileDialog1.FileName; 
            }             saveFileDialog1.Filter = "文本|*.txt"; 
            if (saveFileDialog1.ShowDialog() == DialogResult.OK) 
            { 
                string _SaveFilePath = saveFileDialog1.FileName; 
            }记事本使用RICHTEXT

下面的代码能够实现读写文本文件的功能
 //打开文本文件并将指定路径下的文件内容读出到文本框中
            OpenFileDialog ofd = new OpenFileDialog();//
            ofd.Filter = "txt.txt|*.txt";
           
            if(ofd.ShowDialog()==DialogResult.OK)
            {
            string ofilepath = ofd.FileName;
            StreamReader sr = new StreamReader(ofilepath,Encoding.GetEncoding("GB2312"));
            this.txtBoxNotepad.Text = sr.ReadToEnd();//txtBoxNotepad文本框
            sr.Close();
            }
  //文本框的内容写入到指的定路径
            SaveFileDialog sfd = new SaveFileDialog();
            sfd.Filter = "txt.txt|*.txt";
            if(sfd.ShowDialog()==DialogResult.OK)
            {
                string sfilepath = sfd.FileName;
                StreamWriter sw = new StreamWriter(sfilepath, true, Encoding.GetEncoding("GB2312"));
                sw.WriteLine(this.txtBoxNotepad.Text);
                sw.Flush();
            }   
可以将保存的内容插入到数据库中